Anti-Nucleophosmin

Nucleophosmin (NPM1) is a multifunctional, ubiquitously expressed nucleolar phoshoprotein which shuttles continuously between the nucleus and cytoplasm and plays an important role in cell proliferation and apoptosis. This protein exerts its functions through the interaction with a multiplicity of biological partners, specifically recognizes DNA G-quadruplexes through its C-terminal region. It is mainly localized in the nucleolus and has been reported to be overexpressed in many types of human cancer, including colon, ovarian, prostate and gastric cancer. Mutations at exon 12 of NPM1 gene is a hallmark of cytogenetically normal acute myeloid leukemia. Protein function: Involved in diverse cellular processes such as ribosome biogenesis, centrosome duplication, protein chaperoning, histone assembly, cell proliferation, and regulation of tumor suppressors p53/TP53 and ARF. Binds ribosome presumably to drive ribosome nuclear export. Associated with nucleolar ribonucleoprotein structures and bind single-stranded nucleic acids. Acts as a chaperonin for the core histones H3, H2B and H4. Stimulates APEX1 endonuclease activity on apurinic/apyrimidinic (AP) double- stranded DNA but inhibits APEX1 endonuclease activity on AP single-stranded RNA. May exert a control of APEX1 endonuclease activity within nucleoli devoted to repair AP on rDNA and the removal of oxidized rRNA molecules. In concert with BRCA2, regulates centrosome duplication. Regulates centriole duplication: phosphorylation by PLK2 is able to trigger centriole replication. Negatively regulates the activation of EIF2AK2/PKR and suppresses apoptosis through inhibition of EIF2AK2/PKR autophosphorylation. Antagonizes the inhibitory effect of ATF5 on cell proliferation and relieves ATF5-induced G2/M blockade (PubMed:22528486). In complex with MYC enhances the transcription of MYC target genes (PubMed:25956029). [The UniProt Consortium]